Condenser and method of making the same



Sept. 11,1923. 1,467,777

P. E. DEMMLER CONDENSER AND METHOD OF MAKING THE SAME Filed Feb. 15 1919 WITNESSES: INVENTOR ffJa/mw/ Pau/ E Demm/er ATTORNEY Patented sem.11,.19z3,.

' UNITED STATES mum .ornca.

PAULE. nmmn, OI PITTSBURGH, PENNSYLVANIA, ASSIGH'OB T mTIHGKOUll ELECTRIC & murac'runmo COMPANY,

A COPIOBATION OI PENNSYLVANIA.

oommnsna m rm'rnon or mine 'rnn sum.-

Application 111.4 !ebrnary 1a, 1919. mm Io. 27am.

Same, of which the following isa specification.

My invention relates to condensers, and it has, for its primary object, the, provision of a method by which a product of high elficiency and exceptional durability may be formed.

One object of my invention is to so wind alternate sheets of foil and an insulating material as to form a condenser of desired capacity and to so dispose the windings as to provide an exceptionally large contact area for the terminals thereof.

Another object of my invention is to construct condensers in which the conducting material shall be disposed in as close relation as possible and thereby obtain a high efliclenc A s till further object of my invention is to construct a condenser of material which will insure a good product and which is readily available and comparatively inexpensive.

With these and other objects in view, my invention will be more fully described, illustrated in the drawings, in the several views of which corresponding numerals indicate like parts, and then particularly pointed out in the claims.

In the drawings, Fig, 1 is a plan view, parts being broken awa of strips of material assembled in rea iness to be formed into a condenser in accordance with my invention; Fig. 2 is a sectional view of the windings of material constituting a condenser embodying my invention, and Fig. 3 is a sectional view taken substantially along the line III-J11 of Fig. 2.

In practising my invention, I may con-' struct 'a condenser by employing metal foil and strips or sheets of insulating material. The sheets of insulating material and foil may be assembled in alternate relation, with the foil sheets referably staggered, so that the edges of a ternate sheets shall project from op ositeedges of the assembled material. e material thus assembled then be wound to the desired shape and subjected to'treatmen't in a bath of any suitable high dielectric strength, as we tively moltenwax to expel the air from between the several windings. The edges of the foil projecting' from the superimposed windings may be pressed together to rovide a lar 0 area of conducting materia to which t e terminals of the condenser may be fastened.

By staggerin the metal foil sheets comprismgthe con enser, exceptionally good ter-' minal contacts are are materially reduced and, consequently, the efliciency is increased.

In Fig. 1' are shown strips'offoil 1 and strips of insulating material 2 assembled preparatory to winding them to form a condenser. As here shown, the strips of metal rovided and, for this reason, the electric osses of the condenser foil 1 are disposed in staggered relation" so that the edges 3 of alternate foilsheets ruect from opposite sides-of the assem led material. The foil sheets may be made of any suitable material, such as aluminum or an alloy. of lead and tin, and the insulating sheets may be an suitable material sessing sufiicient dielectric strength an sufficient pliability to permit of being wound in superposed relation. j

I have found, however, that an insulating material which may be employed to great advantage may a metal foil to a bath ofbaking varnish. The metal foil may be drawn through the bath of baking varnish and through a drying tower to harden the film of varnish which will adhere to the foil. This operation of treating the metal foil in the bath of varnish and in a drying tower maybe repeated as often as desired to obtain the reuired thickness of film on the foil. The 1m of varnish on the foil may therefrom to obtain a relative y thin sheet of insulating material which possesses a l as being tough and pliable.

As shown in Fig. 2, the foil 1, shown in cross section and the insulating material 2,

shown in elevation to clearly distinguish them, may be wonndto form a comparafiat body 4 having rounded end portions 5. After the material has been wound, it may be subjected to treatment in a bath of molten Wax in order to ex 1 the air from between the windings. Elie wound condenser may then have its projecting edge portions 3 of the metal foil pressed together and secured in place as indicated at 6. Terbe provided bysubjectingbe removed I minals may be connected to the condenser along the connected ed e rtions and, by so doin an exceptional y urge contact area may e provided, on account of the fact that the terminals engage the foil outtheir entire widths.

In Figs. 2 and 3, the thicknesses of the insulating material and the foil are shown as greatly exagerated in order to clearly dlsclose the disposition of the different materials. It will be obvious, however, that the metal foil and the insulating material, being both relatively thin, form a flat body having projecting edge portions of foil which may be easily pressed together to provide the desired contact surfaces. A condenser thus formed may, of course, be disposed within a suitable casing, not shown in the drawings. The casing ma be of any insulating material having su cient mechanical strength to protect the windings from insheets through- J lthough I have specifically described a condenser formed in accordance with my invention, it is obvious that sli ht changes may be made in 'the construction thereof,

without departing from the spirit of m invention, and I desire, therefore, that no imitations shall be imposed except such as are indicated in the appended claims.

I claim as my invention:

1. A condenser comprising superimposed windings of a plurality of alternate strips of metal foil and a plurality of self-sustaining flexible stri s of hardened varnish, the strips of foil being disposed in stag ered relation with respect to each other and the pro.- jecting edge portions of the several convolutions of each foil being secured together.

2, A condenser comprising superimposed windings of a pluralit of alternate strips of metal foil and a p urality of strips of self-sustainin baking varnish, the strlps of foil being dlsposed in staggered relation with respect to each other, the projecting edge portions of the several convolutions of each foil being secured together, and the windings being embedded in a suitable wax.

In testimony whereof, I have hereunto subscribed my name this 31st day of Jan.,

PAUL E. DEMMLER. 

